Section 816 Soil Aggregate Bases

816.1 General Description
Section 816—Soil Aggregate Bases
This section includes the requirements for material to be used as soil aggregate base.
816.1.01 Related References
A. Standard Specifications
Section 815—Graded Aggregate
B. Referenced Documents
AASHTO T 89
AASHTO T 90
GDT 4
GDT 6
GDT 7
GDT 13
816.2 Materials
816.2.01 Soil Aggregate
A. Requirements
1. Type
Use a soil aggregate base, subbase, or shoulder base course material that is of uniform quality.
2. Material Retained on No. 10 (2 mm) sieve
Ensure the material retained on the No. 10 (2 mm) sieve meets the requirements of Subsection 815.2.01.A.
NOTE: You may substitute Group I graded aggregate base that meets the requirements of Subsection
815.2.01.A for soil aggregate base.
3. Gradation
Ensure the soil aggregate base, subbase, or shoulder material meets the following gradation:
Size
Percent by Weight
Passing 2 in (50 mm) sieve 100
Passing 1-1/2 in (37.5 mm) sieve 95-100
Passing 3/4 in (19 mm) sieve 60-97
Passing No. 10 (2 mm) sieve 25-55
Material passing No. 10 (2 mm) sieve
Passing No. 10 (2 mm) sieve 100
Passing No. 60 (250 µm) sieve 15-85
Passing No. 200 (75 µm) sieve (silt less clay) 3-25
Clay (8 minutes suspension on elutriation test) 10-25
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Section 816—Soil Aggregate Bases
B. Fabrication
Ensure that the material passing the No. 10 (2 mm) sieve has a total volume change of 15 or less.
Ensure that the material passing the No. 40 (425 µm) sieve has a Liquid Limit (LL) of 25 or less and a Plasticity
Index (PI) of 9 or less.
General Provisions 101 through 150.
C. Acceptance
Test as follows:
Test
Method
Gradation GDT 4 and GDT 13
Volume change GDT 6
Liquid limit AASHTO T 89
Plastic limit and plasticity index AASHTO T 90
D. Materials Warranty
General Provisions 101 through 150.
816.2.02 Soil Mortar for Soil Aggregate Base
A. Requirements
Use a soil mortar for soil aggregate bases of friable materials meeting these requirements:
Percent passing No. 200 (75 µm) sieve 0-65
Volume change 0-15
Maximum dry density 95 lb/ft³+ (1520 kg/m³ +)
B. Fabrication
General Provisions 101 through 150.
C. Acceptance
Test as follows:
Test
Method
Gradation GDT 4
Volume change GDT 6
Maximum dry density GDT 7
D. Materials Warranty
General Provisions 101 through 150.
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